Ah, yes. One of the other posts got me confused.

But then I know the answer.

Rows and columns are independent. There are 6 ^ 8 = 1679616 possible rows. 1444500 are valid (simple brute force calculation). So, picking a single random row (or column) has a 1444500/1679616 of being valid. The grid has 8 rows and 8 columns. (1444500/1679616)^16 = 0.089561362, which seems to be very close what your program is measuring.

In reply to Re^7: Pattern enumeration. by JavaFan
in thread Pattern enumeration. by BrowserUk

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